A gastric or pancreatic pseudocyst is a localized fluid collection, which may be rich in pancreatic enzymes, surrounded by a thin wall that may develop in the peritoneal cavity after the onset of acute pancreatitis. Although many pseudocysts resolve themselves spontaneously, some pseudocysts become quite large and require treatment due to the unwanted pressure they exert against the stomach and/or neighboring organs.
One approach to treating gastric pseudocysts involves surgery and typically comprises (i) cutting through the abdominal wall of the patient to permit access to the pseudocyst through the abdominal wall, (ii) perforating or puncturing the pseudocyst, (iii) inserting a drainage tube into the pseudocyst through the perforation to allow the contents of the pseudocyst to empty through the drainage tube to a point external to the patient, (iv) removing the drainage tube from the patient once the pseudocyst has been emptied, and (v) repairing the abdominal wall. As can readily be appreciated, the surgical approach described above is invasive and has easily identifiable drawbacks associated therewith, such as an appreciable risk of infection.
In some instances, an endoscopic approach to treating gastric pseudocysts may be utilized. This approach is less invasive than surgery and typically involves inserting an endoscope through the patient's mouth and into the patient's stomach. The endoscope is first used to visually locate the pseudocyst on the opposite side of the stomach wall. A needle or sphincterotome is then extended through the distal end of the endoscope to perforate both the stomach wall and the pseudocyst. A contrast agent delivered through the endoscope is then injected into the pseudocyst, and a cystogram is endoscopically performed to confirm entry into a pseudocyst (as opposed to entry into the peritoneal cavity). Following confirmation of entry into a pseudocyst, a guide wire is advanced through the endoscope and into the pseudocyst. Next, a balloon catheter is advanced through the endoscope and over the guide wire into the pseudocyst. The balloon is dilated to enlarge the perforations in the pseudocyst and the stomach and is then deflated and withdrawn. A plurality of straight endobiliary tubes or stents are then endoscopically implanted across the pseudocyst and stomach perforations to allow the contents of the pseudocyst to drain into the stomach, said biliary tubes or stents being arranged in a side-by-side fashion and being implanted one at a time. The endoscope is then removed from the patient. When drainage is complete (typically within a few weeks), the endoscope is reintroduced into the patient, and the biliary tubes or stents are withdrawn from the patient through the endoscope using a snare.
Although the aforementioned endoscopic approach has certain advantages over the surgical approach described above, the foregoing endoscopic approach still suffers from certain drawbacks. The procedural sequence may involve up to five separate instruments, exchanged through a gastroscope to complete the procedure, making the procedure complex and time consuming.